Refactor shell.ts

core/shell.ts

@@ -1,5 +1,7 @@
+#!/usr/bin/env -S deno run --allow-run
 export interface ShellSpawnerOpts extends Omit<Deno.CommandOptions, 'args'> {
     shell: string
+    prefix?: string
     shellArgs: (commandStr: string) => string[]
     autospawn: boolean,
 }
@@ -13,6 +15,62 @@ export interface ShellSpawnerOpts extends Omit<Deno.CommandOptions, 'args'> {
  */
 export type ShellSpawner<R = Deno.Command> = (a: string | TemplateStringsArray, ...values: unknown[]) => R
 
+class Troopa implements PromiseLike<Deno.CommandOutput> {
+    [Symbol.toStringTag] = 'Promise'
+
+    cmd: Deno.Command
+    #process?: Deno.ChildProcess
+
+    constructor(
+        public cmdStr: string,
+        public opts: ShellSpawnerOpts
+    ) {
+        this.cmd = new Deno.Command(this.opts.shell, {
+            args: this.opts.shellArgs(this.cmdStr),
+            stdin: 'inherit',
+            stdout: 'piped',
+            stderr: 'piped',
+            ...opts
+        })
+    }
+
+    /**
+     * Starts the process, if not yet started.
+     * @author MindfulMinun
+     * @since 2023-12-26
+     */
+    start() { return this.process }
+
+    get process() {
+        if (this.#process) return this.#process
+        this.#process = this.cmd.spawn()
+        return this.#process
+    }
+
+    get  stdin() { return this.process.stdin }
+    get stdout() { return this.process.stdout }
+    get stderr() { return this.process.stderr }
+
+    pipe(into: Troopa): Troopa
+    pipe(into: WritableStream): null
+    pipe(into: Troopa | WritableStream<Uint8Array>): Troopa | null {
+        if (into instanceof Troopa) {
+            this.process.stdout.pipeTo(into.process.stdin)
+            return into
+        }
+
+        this.process.stdout.pipeTo(into)
+        return null
+    }
+
+    then<Resolved = Deno.CommandOutput, Rejected = never>(
+        onfulfilled?: ((a: Deno.CommandOutput) => Resolved | PromiseLike<Resolved>),
+        onrejected?: ((a: unknown) => Rejected | PromiseLike<Rejected>)
+    ): PromiseLike<Resolved | Rejected> {
+        return this.process.output().then(onfulfilled, onrejected)
+    }
+}
+
 /**
  * Run a shell script.
  * Factory facade to easily interact and run shell scripts
@@ -21,12 +79,12 @@ export type ShellSpawner<R = Deno.Command> = (a: string | TemplateStringsArray,
 export default function koopa(opts: Partial<ShellSpawnerOpts> = {}) {
     const actualOpts: ShellSpawnerOpts = {
         shell: 'sh',
-        shellArgs: cmd => ['-c', cmd],
+        shellArgs: cmd => ['-c', `${opts.prefix || 'set -euo pipefail'}; ${cmd}`],
         autospawn: true,
-        ...opts,
+        ...opts
     }
 
-    const factory: ShellSpawner = function (
+    const factory: ShellSpawner<Troopa> = function (
         templ: TemplateStringsArray | string,
         ...values: unknown[]
     ) {
@@ -39,16 +97,20 @@ export default function koopa(opts: Partial<ShellSpawnerOpts> = {}) {
             for (let i = 0; i < templ.length; i++) {
                 execStr += templ[i]
                 execStr += typeof values[i] !== 'undefined'
-                    ? escape('' + values[i])
+                    ? escape(`${values[i]}`)
                     : ''
             }
         }
-
-        return new Deno.Command(actualOpts.shell, {
-            args: actualOpts.shellArgs(execStr),
-            ...opts
-        })
+        return new Troopa(execStr, actualOpts)
     }
 
     return factory
 }
+
+if (import.meta.main) {
+    const $ = koopa({
+        prefix: 'set -euox pipefail',
+    })
+    $`echo 1; sleep 1; echo 2; sleep 1; echo 3;`
+        .pipe(Deno.stdout.writable)
+}